Homeworks

Question 1

Possible causes for decline?

What kind of study would you do to determine which of possible causes is the right one?

Answer 1

• Hunting?
• Disease?
• Carrying capacity over shot

(Depletion of prefered food caused by over population of ibex now they’re struggaling to find enough to stay healthy and fertile. reproductive rate has fallen and survival of adults are threatended)

Weigh the carcus

Check their fat reserves and general condition (skinny or fat and healthy) if they are scrawny and you can see ribs then you can conclude there is a lack of food. If individuals look healthy and females are lactating then reason for decline is likely to be predation.

Question 2

Why haven’t Eucalyptus gone crazy?

Whats holding it back from becoming invasive?

Answer 2

-Aus is hotter and dryer compared to NZ?

Aus = desert NZ = Alpine/Coastal

(climate not suitable and fires not common enough to help with disperal of seeds)

-Eucalyptus are strongly fire adapted?

-Regenerate best after a fire because fire because it created a ‘blank canvas’ which throws masses of light to the dependant Eucalyptus plant.

Eucalyptus not a good seed disperser in NZ?

Eucalyptus not had the same amount of introduction effort as pines?

No suitable pollenators in NZ?

Attacked heavily by some sort of insect out of plantations?